A number of prior attempts have been made to devise arm rests to solve the aforementioned difficulties. More particularly, a wide variety of arm rest constructions have been devised. Most such constructions relate to arm rests which hang or are otherwise dependent from the window frame of a vehicle door. Representative of these are the arm rests shown in U.S. Pat. Nos. 1,695,549, 1,715,862, 1,760,450, 1,873,414, 1,984,855, 2,569,436, 2,577,561, 3,603,637 and 4,592,584.
The aforementioned prior art arm rest arrangements have several deficiencies, one of the most important being the fact that they allow the individual to rest his or her arm at only one level. While some of the patents show arrangements which allow adjustment of the arm rest to different levels, the driver or other vehicle occupant does not have the option of positioning his or her arm at different levels on the arm rest once such adjustment has been made.